“It's so easy to throw these things away,” Johnson crew chief Chad Knaus said. “We see it time and time again. There's things that you cannot control, there's things that you can control, and we've got to make sure that we can control what is in our ability and put our best foot forward.

“If we don't, if we let something slip, it could be a big problem.”

Here are the championship scenarios for the three national series:

Sprint Cup

Johnson leads Kenseth by 28 points and Harvick by 34. Johnson wins the championship if he finishes 23rd or better, 24th or better if he leads a lap or 25th or better if he leads the most laps.

If he struggles or has a problem and finishes worse than those spots, Kenseth and Harvick have a chance. Kenseth, with seven wins, owns the tiebreaker over Johnson (six wins) and Harvick (four wins). Johnson owns the tiebreaker over Harvick.

Each position on the track is worth one point with drivers who lead a lap getting one bonus point apiece, the driver who leads the most laps getting another bonus point and the winning driver earning an additional three bonus points. If there is a tie for most laps led, each of those drivers earns a bonus point.

So if none of the three drivers wins the race, Kenseth must beat Johnson by 28 spots and not lose to Harvick by seven spots, give or take two spots depending on if either leads a lap or the most laps. Harvick must beat Kenseth by seven spots and Johnson by 35, give or take two spots.

If Kenseth wins and leads the most laps, he wins the title if Johnson finishes lower than 23rd, lower than 24th if he leads a lap or lower than 25th if he leads the most laps.

If Kenseth wins and doesn’t lead the most laps, he wins the title if Johnson finishes lower than 24th, lower than 25th and leads a lap, or lower than 26th and leads the most laps.

If Harvick wins and leads the most laps, Johnson would have to finish lower than 30th, lower than 31st with one lap led or lower than 32nd with the most laps led; AND Kenseth would have to finish lower than second, lower than third with one lap led, or lower than fourth with the most laps led.

If Harvick wins and doesn’t lead the most laps, he wins the title if Johnson finishes lower than 31st, lower than 32nd with one lap led, or lower than 33rd with the most laps led; AND Kenseth would have to finish lower than third, lower than fourth with one lap led, or lower than fifth with the most laps led.

Nationwide Series

Austin Dillon has an eight-point lead over Sam Hornish Jr.

With one win for Hornish this year and Dillon having none, Hornish owns the tiebreaker.

If Hornish wins the race and leads the most laps, Dillon still wins the title if he finishes third, fourth if he leads a lap or fifth if he leads the most laps. If Hornish wins the race but does not lead the most laps, then Dillon just needs to finish fourth or fifth.

If Hornish doesn’t win, then he must beat Dillon by eight spots, give or take one or two spots depending on whether either of them leads a lap and/or leads the most laps.

Camping World Truck Series

Matt Crafton leads by 46 points over Ty Dillon. Because there are only 36 trucks that start a race, Crafton will clinch the title just by starting the race. If he does not start the race, Dillon would have to win the race to win the championship.